Digital watermarks are one of the technologies being touted as a means to deter piracy of digital content. The issue with watermarks is that they're subject to abuses that could invade an innocent consumer's privacy or, worse, expose him to lawsuits for infringements he did not commit.

For this reason it's paradoxal to use digital watermarks in ebooks. It's all in all paradoxal to fight against piracy at all. The history of piracy and the music industry shows, the way it goes: If there are good legal offers for the customers, piracy will reduce till it is insignificant.